Insulin is a naturally occurring hormone produced by the human pancreas whose main function is to regulate circulating levels of glucose in the blood stream. Insulin administration is the most common form of pharmacology therapy in patients with diabetes aimed at reducing blood sugar levels in these patients. While current insulin preparation have been extremely useful, all have the property of forming crystals at the injection site, causing the absorption of insulin from the subcutaneous tissue into the blood steam to be delayed. Eli Lilly has recently engineered a form of insulin which does not crystallize under the skin and, therefore, gets absorbed more rapidly and more predictably in patients with diabetes. This form of insulin, called lispro insulin, has been extensively used around the world in a number of clinical trials and is currently approved for use in a number of European countries. The current study is designed to examine the absorption and action profiles of lispro insulin in patients with diabetes who have impaired renal function. Because the kidney participates in the clearance of insulin, patients with renal failure might be expected to have higher levels of circulating insulin than non renal failure patients following injection. While this has been a clinically insignificant problem with the current insulin formulations, it is not known whether Lispro behaves similarly in diabetic patients with renal failure. Therefore, the primary objective of this study is to test whether the pharmacologic properties of lispro insulin are maintained and predictable in patients with renal failure as they are in patients without renal failure.